Inflation device

ABSTRACT

An inflation device for inflating containers having a body with an air channel therein being in the form of a venturi tube. A first inlet is provided in the body, being in communication with the air channel, to allow compressed air to flow into the air channel. An outlet is provided in the body, being in communication with the air channel, to allow the air to exit the air channel for inflating a container joined to the outlet. A second inlet is provided in the body, being in communication with the first inlet, to allow ambient air to be sucked into the air channel as a result of the compressed air flowing in the air channel and passing through the venturi tube. A self-closing valve and sensor means are also provided.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation of PCT International Application PCT/IB2010/051762 filed Apr. 22, 2010, which in turn claims the benefit of South African Patent Application No. ZA 2009/03257 filed on May 12, 2009, the entire disclosures of both of which are incorporated herein by reference.

FIELD OF INVENTION

The present invention relates to an inflation device.

More particularly, the invention relates to an inflation device for inflating containers with non-rigid-walls, such as dunnage bags.

BACKGROUND TO INVENTION

Inflatable dunnage bags are commonly used for cushioning loads shipped in trucks, trailers and containers transported by ships, trucks or rail. This is often the case when the cargo only partially fills the container and there exists the possibility of shifting during transport that could cause damage. Typically known dunnage bags are constructed of one or more layers of paper or woven polypropylene surrounding a plastic lining. The paper protects the bags from tearing—thus more layers are used in applications where the risk of damage to the dunnage bag is greater. Furthermore, for inflating and deflating the dunnage bag, a valve is attached by way of a hole cut in the bag during manufacture.

The dunnage bags are shipped flat from the manufacturer, and are inflated by packing and loading personnel as the containers are loaded with cargo. The bag is firstly placed in the space that it will occupy as cargo is loaded into a container, secondly the inflation device is attached to valve of the dunnage bag and subsequently the dunnage bag is filled with air until an appropriate air pressure within the bag is achieved. Typically this occurs within a few seconds.

Various types of inflation devices exist for inflating containers with non-rigid walls and air-filled bags, such as sacks and dunnage bags commonly used to cushion cargo loads. Known inflation devices include tire inflation tools which have been converted or adapted and are attached to a hose leading from a source of compressed air. Some inflation devices incorporate venturi tubes and are often known as venturi air-flow guns, which include a venturi tube, namely an air passage with a region of restricted diameter. In terms of Bernoulli's law (i.e. the inverse relationship between air velocity and pressure), passage of air through the restricted region of a venturi tube creates a low-pressure region resulting in a suction effect used to draw air out of an attached container.

Unfortunately the known type of inflation devices are difficult to operate and not flexible in operation and thus suffer from important limitations. Furthermore in practice it must be ensured that an inflated bag is fully inflated.

PCT/IB2009/050851 STOPAK (PTY) LTD et al discloses an inflation device for inflating containers with non-rigid walls such as bags, which includes a body having a venturi shaped air channel. First and second air inlets lead into the air channel, with an outlet being adapted to allow air to exit from the air channel for inflating a container when joined to the outlet. The second inlet is adapted to be closed by a self-closing valve if air does not flow through the air channel. A sensor associated with the body is adapted to detect when a container, such as a bag, joined to the body has been filled to a predetermined degree and then causes the flow of air through the air channel to be interrupted automatically. Unfortunately this inflation device is expensive and requires electricity and batteries to operate which often are not available at the sites where dunnage bags are inflated.

It is an object of the invention to suggest an inflation device which will assist in overcoming the aforesaid problems.

SUMMARY OF INVENTION

According to the invention, an inflation device for inflating containers with non-rigid walls such as bags, includes

-   -   (a) a body;     -   (b) an air channel provided in the body and having appropriate         first and second open ends;     -   (c) a venturi tube in the body and being in communication with         the first and second open ends of the air channel;     -   (d) a first inlet in the body and being in communication with         the air channel and the venturi tube and being adapted to allow         compressed air to enter the venturi tube via the air channel to         the second open end;     -   (e) an outlet in the body and being in communication with the         second open end of the air channel via the venturi tube and         being adapted to allow air to exit from the venturi tube for         inflating a container when joined to the outlet;     -   (f) a second inlet in the body and being in communication with         the first open end of the air channel and being adapted to allow         ambient air to be sucked into the venturi tube as a result of         compressed air entering the air channel and passing through the         venturi tube;     -   (g) a first self-closing valve located at the second inlet in         the body and being adapted to close off the second inlet if the         pressure in the air channel is greater than the ambient         pressure;     -   (h) a sensor means associated with the body and being adapted to         indicate the pressure in a container, such as a bag, joined to         the body; and     -   (i) a manually operable valve means being adapted cause the         supply of compressed air into the air channel to be interrupted.

Also according to the invention, an inflation device for inflating containers with non-rigid walls, includes

-   -   (a) a body;     -   (b) an air channel provided in the body and having opposite         first and second open ends;     -   (c) a venturi tube in the body and being in communication with         the first and second open ends of the air channel;     -   (d) a first inlet in the body and being in communication with         the air channel and the venturi tube and being adapted to allow         compressed air to enter the venturi tube via the air channel to         its second open end;     -   (e) an outlet in the body and being in communication with the         second open end of the air channel via the venturi tube and         being adapted to allow air to exit from the venturi tube for         inflating a container when joined to the outlet;     -   (f) a second inlet in the body and being in communication with         the air channel and being adapted to allow ambient air to be         sucked into the venturi tube as a result of compressed air         entering the air channel and passing through the venturi tube;     -   (g) a first self-closing valve located at the second inlet in         the body and being adapted to close off the second inlet if the         pressure in the air channel is greater than the ambient         pressure;     -   (h) a shut-off valve in the container, such as a bag, and being         in communication with the air channel;     -   (i) a sensor means associated with the body and being adapted to         indicate continuously the pressure in a container, such as a         bag, joined to the body; and     -   (j) a manually operable valve means being adapted cause the         supply of compressed air into the air channel to be interrupted.

Yet further according to the invention, there is provided a method of inflating containers with non-rigid walls, such as bags, includes the steps

-   -   (a) of joining the outlet of an inflation device as set out         herein to the inlet of a container to be inflated;     -   (b) of allowing compressed air to enter the first inlet for         inflating the container;     -   (c) of sucking air into the second inlet by means of a venture         tube;     -   (d) of determining and indicating the pressure in the container;     -   (e) of manually interrupting the supply of compressed air into         the container by manually operable valve means; and     -   (f) of removing the container when the compressed air supply has         been interrupted manually.

The manually operable valve means may include a ball valve and/or a spring operated trigger valve and/or a shut-off valve.

The inflation device may also be used to deflate the containers, whereby the first self closing valve is removed and/or disabled and the venture tube is reversed.

The sensor means may be adapted to continuously indicate the pressure inside the container whilst the container is being inflated.

The inflation device may be a venturi-air flow apparatus or gun. The venturi tube may include a supersonic nozzle.

In use the air exiting the outlet may have an absolute pressure of about 0 to 9 bar.

In use the compressed air entering the air channel may have a pressure of up to 9 bar absolute.

The supersonic nozzle may be a shock-free type.

The inflation device may be used as a high speed inflator operating at low pressure.

In use the operating pressure of the inflation device may be about 9 bar absolute.

The body may have a flange for securing the inflation valve to the container.

The container may be a dunnage bag, a sack and/or any other flexible container to be pressurized.

The body may include threads suitable for cooperating with complementary threads of a container's inlet.

The device may include a valve connector assembly attached to the outlet of the air channel, which is adapted to be releasably engaged to a valve.

The venturi tube may include a frusto-conical bore.

The first inlet may be adapted to receive an air hose for supplying compressed air.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be described by way of example with reference to the accompanying schematic drawings.

In the drawings there is shown in

FIG. 1 a perspective view of an inflation device in accordance with the invention.

FIG. 2 a section top view of the inflation device as seen from arrows II-II in FIG. 1;

FIG. 3 a second perspective view of the inflation device shown in FIG. 1, whereby the inflation device is adapted to be a deflator;

FIG. 4 a sectional side view of the inflation device as seen from arrows IV-IV in FIG. 3, whereby the inflation device is adapted to be a deflator;

FIG. 5 a perspective view of the air channel of the inflation device as shown in FIG. 1;

FIG. 6 a side view of the air channel of the inflation device as seen from arrow VI in FIG. 5; and

FIG. 7 a sectional side view of the air channel of the inflation device as seen from arrows VII-VII in FIG. 5.

DETAILED DESCRIPTION OF DRAWINGS

Referring to the drawings, an inflation device in accordance with the invention, generally indicated by reference numeral 10, is shown.

The inflation device 10 is intended for inflating containers with non-rigid walls such as bags.

The inflation device 10 includes

-   -   (a) a body 12;     -   (b) an air channel 14 provided in the body and having         appropriate open ends 16 and 18;     -   (c) a venturi tube 20 in the air channel 14 and being in         communication with the first open end 16 and second open end 18         of the air channel 14;     -   (d) a first inlet 22 in the body 12 and being in communication         with the air channel 14 and the venturi tube 20 and being         adapted to allow compressed air to enter the venturi tube 20;     -   (e) an outlet 24 in the body 12 and being in communication with         the open end 18 of the air channel 14 and being adapted to allow         air to exit from the air channel 14 and venturi tube 20 for         inflating a container when joined to the outlet 24;     -   (f) a second inlet 26 in the body 12 and being in communication         with the air channel 14 and being adapted to allow ambient air         to be sucked into the venturi tube 20 as a result of compressed         air entering the air channel 14 and passing through the venturi         tube 20;     -   (g) a first self-closing valve 28 located at the second inlet 26         in the body 12 and being adapted to close off the second inlet         26 if the pressure in the air channel 14 is greater than the         ambient pressure; and     -   (h) a sensor means 30 associated with the body 12 and being         adapted to indicate continuously the pressure in a container,         such as a bag, joined to the body 12; and     -   (i) a manually operable valve means 38 being adapted cause the         supply of compressed air into the air channel to be interrupted.

The body 12 furthermore has a handle 32 for suitably gripping and holding the inflation device 10 during filling of a bag.

The sensor means 30 is adapted to continuously indicate the pressure inside the container whilst the container is being inflated.

The inflation device 10 can also be used to deflate containers whereby the first self closing valve is removed and/or disabled and the venture tube is reversed as can be seen from FIGS. 3 and 4.

The inflation device 10 is typically in the form of a venturi-air flow apparatus or gun.

The venturi tube 20 includes a supersonic nozzle 34, which is of a shock-free type.

In use the air exiting the outlet 24 can have an absolute pressure of about 9 bar.

In use the compressed air entering the air inlet 22 can have a pressure of about 9 bar absolute.

The outlet 24 is adapted to be releasably engaged to an inlet valve of a container to be inflated.

The fitting 36 connected to the first inlet 22 is adapted to be coupled to an air hose. It is also provided with a second self closing valve (not shown). This second self closing valve is adapted to close off the first inlet 22, e.g. when caused to do so by the operator.

The venturi tube 20 has a first self-closing valve 28 at the second inlet 26 adapted to assist in closing the inlet 26 to the venturi tube 20.

The container to be inflated can be a dunnage bag, a sack and/or any other flexible container to be pressurized. The container is generally provided with a valve having a flange for securing the outlet 24 to the container. The valve is generally a one-way or semi-one way valve.

The inflation device 10 in accordance with the invention can be used as a high speed inflator operating at low pressure for inflating containers having non-rigid walls. The operating pressure of the inflation device 10 typically is about 9 bar absolute.

The air channel 14 may also be provided with a pressure relief valve.

The inflation device 10 in accordance with the invention, thus provides a method of inflating containers with non-rigid walls, which includes the steps

-   -   (a) of coupling the fitting 36 to a compressed air supply tube;     -   (b) of coupling the outlet 24 to a bag to be inflated;     -   (c) of allowing compressed air to enter through a first inlet         22;     -   (d) of allowing air to be sucked through the second inlet 26         into venturi tube 20, as a result of the compressed air entering         the air channel 14; and     -   (g) of determining and indicating the pressure in the container;     -   (h) of manually interrupting the supply of compressed air into         the container by manually operable valve means 38; and     -   (i) of removing the container when the compressed air supply has         been interrupted manually.

LIST OF REFERENCE NUMERALS

10 inflation device

12 body

14 air channel

16 first open end

18 second open end

20 venturi tube

22 first inlet

24 outlet

26 second inlet

28 first self-closing valve

30 sensor

32 handle

34 supersonic nozzle

36 fitting

38 manually operable valve means 

1. An inflation device for inflating containers with non-rigid walls such as bags, which includes (a) a body; (b) an air channel provided in the body and having appropriate first and second open ends; (c) a venturi tube in the body and being in communication with the first and second open ends of the air channel; (d) a first inlet in the body and being in communication with the air channel and the venturi tube and being adapted to allow compressed air to enter the venturi tube via the air channel to the second open end; (e) an outlet in the body and being in communication with the second open end of the air channel via the venturi tube and being adapted to allow air to exit from the venturi tube for inflating a container when joined to the outlet; (f) a second inlet in the body and being in communication with the first open end of the air channel and being adapted to allow ambient air to be sucked into the venturi tube as a result of compressed air entering the air channel and passing through the venturi tube; (g) a first self-closing valve located at the second inlet in the body and being adapted to close off the second inlet if the pressure in the air channel is greater than the ambient pressure; (h) a sensor means associated with the body and being adapted to indicate continuously the pressure in a container, such as a bag, joined to the body; and (i) a manually operable valve means being adapted to cause the supply of compressed air into the air channel to be interrupted.
 2. A device as claimed in claim 1, in which the manually operable valve includes a ball-valve and/or spring-operated trigger valve and/or a shut-off valve.
 3. A device as claimed in claim 1, which is adapted to be used to deflate the containers, whereby the first self closing valve is removed and/or disabled and the venture tube is reversed.
 4. A device as claimed in claim 1, in which the sensor means is be adapted to continuously indicate the pressure inside the container whilst the container is being inflated.
 5. A device as claimed in claim 1, which is a venturi-air flow apparatus or gun.
 6. A device as claimed in claim 1, in which the venturi tube includes a supersonic nozzle.
 7. A device as claimed in claim 1, in which in use the air exiting the outlet has an absolute pressure of about 0 to 9 bar.
 8. A device as claimed in claim 1, in which in use the compressed air entering the air channel has a pressure of up to 9 bar absolute.
 9. A device as claimed in claim 6, in which the supersonic nozzle is a shock-free type.
 10. A device as claimed in claim 1, which is adapted to be used as a high speed inflator operating at low pressure.
 11. A device as claimed in claim 1, in which in use the operating pressure of the inflation device is about 9 bar absolute.
 12. A device as claimed in claim 1, in which the body includes a flange for securing the inflation valve to the container.
 13. A device as claimed in claim 1, in which the container is a dunnage bag, a sack and/or any other flexible container to be pressurized.
 14. A device as claimed in claim 1, in which the body includes threads suitable for cooperating with complementary threads of a container's inlet.
 15. A device as claimed in claim 1, which includes a valve connector assembly attached to the outlet of the air channel, which is adapted to be releasably engaged to a valve.
 16. A device as claimed in claim 1, in which the venturi tube includes a frusto-conical bore.
 17. A device as claimed in claim 1, in which the first inlet is adapted to receive an air hose for supplying compressed air.
 18. A method of inflating containers with non-rigid walls, such as bags, which includes the steps (a) of joining the outlet of an inflation device as set out herein to the inlet of a container to be inflated; (b) of allowing compressed air to enter the first inlet for inflating the container; (c) of sucking air into the second inlet by means of a venture tube; (d) of determining and indicating the pressure in the container; (e) of manually interrupting the supply of compressed air into the container by manually operable valve means; and (f) of removing the container when the compressed air supply has been interrupted manually. 